The overall objectives of the research program are (1) to elucidate the influence and significance of ambient temperature and host cell on replication of viruses associated with the Lucke renal adenocarcinoma, and (2) to determine the nature and function of virus-induced macromolecules and determine what effect these macromolecules have in controlling viral and host cell functions. Results showed that thermosensitivity of initiation and replicatin of polyhedral cytoplasmic deoxyvirus (PCDV) DNA is regulated differently in unrelated host cells. Other data indicate that DNA-dependent RNA polymerase (transcriptase) activity is associated with virus cores and the enzyme is active in vitro at temperatures non-permissive (37 C) for virus DNA replication. However, translation of mRNA into proteins needed for initiation of viral DAN synthesis are not synthesized at 37 C. Using rate zonal centrifugation techniques, viral DNA replicative complexes active in transciption and replication of DNA in vitro have been isolated from infected cells. Further experiments are planned to investigate the nature and function of proteins associated with virus particles and viral DNA replicative complexes from infected cells incubated at temperatures permissive (28 C) and nonpermissive (34 C and 37 C) for virus multiplication.